Shear knives and holding means therefor

ABSTRACT

A shear knife is provided of generally rectangular form having a plurality of spaced openings through the knife intermediate its width from end to end, each provided with a countersunk portion at each end separated by a land defining an elongated pass through portion and fastener means having an elongated stem and cut-away frusto conical head adapted to pass through the opening in the shear knife and can be rotated 90* to lock the knife in place.

United States Patent 1191 Murray Nov. 4, 1-975 SHEAR KNIVES AND HOLDING MEANS THEREFOR [75] Inventor: C. Wesley Murray, Pittsburgh, Pa.

[73] Assignee: Midvale-Heppenstall Company, Pittsburgh, Pa.

22 Filed: June 12,1974

21 Appl. No.: 478,624

[52] US. Cl. 83/698 [51] Int. Cl. B26D 1/00; B26D 7/26 [58] Field of Search 83/698, 355, 356.3

[56] References Cited UNITED STATES PATENTS 1,569,136 l/1926 Pardee, .lr 83/698 x 2,814,345 11/1957 Repper 83/698 X 3/1960 Whistler, Sr. et a1 83/698 X 7/1962 Thompson 83/698 11/1963 Kraft et a1 83/698 X Primary ExaminerWillie G. Abercrombie Attorney, Agent, or Firm-Buel1, Blenko & Ziesenheim [57] ABSTRACT A shear knife is provided of generally rectangular form having a plurality of spaced openings through the knife intermediate its width from end to end, each provided with a countersunk portion at each end separated by a land defining an elongated pass through portion and fastener means having an elongated stem and cut-away frusto conical head adapted to pass through the opening in the shear knife and can be rotated 90 to lock the knife in place.

4 Claims, 6 Drawing Figures US. Patent Nov. 4, 1975 SHEAR KNIVES AND HOLDING MEANS THEREFOR This invention relates to shear knives and holding means therefor and particularly to a double cutting edge shear knife that can be used on both right and left hand shears and to a means for holding such shear knives in position on the shears.

Shears and shear knives used in shearing steel sheets, bars, rods and the like have taken many forms over the years. In the case of shears used in conjunction with bar mills for shearing bars, it is common to use different shear knives for the right hand and left hand shears. Moreover, such knives have had only a single cutting edge and there has been no way to quickly and easily fasten or remove the shear knives from the shears.

The present invention is designed to provide a solution to all of these problems. It provides a shear knife which can be used on either left or right hand shears. It provides a knife with two cutting edges. And finally, it provides a new holding means for such shear knives.

Preferably, I provide an elongated shear knife of generally rectangulanform, a plurality of spaced openings through said knife intermediate its width from one end to the other in the longitudinal direction, each such opening provided with a like countersunk portion at each end separated by a land and with an elongated pass through portion, a longitudinal extending hole in at least one end of said knife, a transverse hole through the knife intersecting the longitudinal hole, a locking member adapted to pass through said hole and a lift lug adapted to enter the longitudinal hole and receive the lock member. Preferably, the shear knife is held in the knife seat by a plunger bolt having a bolt body having a countersink head machined at opposite sides to the thickness of the bolt body so as to pass through the oblong hole in the shear. These bolts are inserted by a hydraulic cylinder through the oblong openings, rotated 90 and clamped in place in the countersunk recess.

In the foregoing general statement I have set out certain objects, purposes and advantages of this invention. Other objects, purposes and advantages will be apparent from a consideration of the following description and the accompanying drawings in which:

FIG. 1 is a side elevational view of a shear knife according to this invention;

FIG. 2 is a fragmentary elevational view of the shear knife of FIG. 1 at the fastening means;

FIG. 3 is a fragmentary section on the line III-III of FIG. 2;

FIG. 4 is a fragmentary elevational view of the lifting lug that is inserted into the elongated hole in the end of the knife (see FIG. 5) for lifting the knife into or out of the shear;

FIG. 5 is an enlarged fragmentary end elevation of the shear knife of FIG. 1, showing the elongated lifting hole. It is this female design that converts the knife into a universal type allowing it to be used in a right or left hand shear; and

FIG. 6 is an enlarged fragmentary side elevation of the shear knife end of FIG. 5.

Referring to the drawings, I have illustrated a shear knife 10 of generally elongated rectangular form having spaced oblong openings 11 along its length, countersunk at each end 12 and 13 and adapted to receive plunger type bolts 14 having a tapered head 15 adapted to match the countersink 12 and 13 of the shear knife and machined on opposite sides to the diameter of the bolt 14. The bolts 14 are inserted by a hydraulic cylinder (not shown), through the oblong holes 11 and rotated 90 to clamp the shear knife in the knife seat 11. The countersunk portions 12 and 13 at each opening 11 are separated by a land 16. This arrangement permits the shear knife to be reversed and thus provides an opposite cutting edge, something which has heretofore not been available.

In order to handle the shear knife, I have eliminated the lifting arm on one end which is conventional in shear knives of the past and have provided at each end of the knife an oblong hold 20 machined into the knife end. A lifting lug 21 is provided for use on conventional handling equipment. The lifting lug 21 is provided with a tongue portion 22 adapted to fit snugly within the oblong hole 20 at each end of the knife. A lock pin 23 is provided to pass through drilled holes 24 in the shear knife intersecting oblong hole 20 and passing through a drilled hole 25 in tongue 22 to lock the tongue in place in the oblong hole 20 of the shear knife. The lifting lug 21 and cooperating oblong hole 20 in the shear knife are used with conventional equipment at the shear for placing the shear knife in position for fastening. This arrangement permits the shear knife to be used either in a right or left hand shear, something which cannot be done with conventional shear knives.

In the foregoing specification, I have set out certain preferred embodiments and practices of my invention, however, it will be understood that this invention may be otherwise embodied within the scope of the following claims.

I claim:

1. An elongated shear knife of generally rectangular form having a plurality of spaced openings through said knife intermediate its width from one end to another, each said opening being provided with a like countersunk portion at each end separated by a land defining an elongated pass through portion and fastener means having an elongated stern portion and a frusto conical head, said head being cut away at opposite sides to pass through the elongated pass through portion of the openings in said sheer knife, the two ends of said shear knife being provided with a longitudinally extending opening receiving a lifting lug. 

1. An elongated shear knife of generally rectangular form having a plurality of spaced openings through said knife intermediate its width from one end to another, each said opening being provided with a like countersunk portion at each end separated by a land defining an elongated pass through portion and fastener means having an elongated stem portion and a frusto conical head, said head being cut away at opposite sides to pass through the elongated pass through portion of the openings in said sheer knife, the two ends of said shear knife being provided with a longitudinally extending opening receiving a lifting lug.
 2. A shear knife as claimed in claim 1 wherein locking means are provided between said lifting lug and opening.
 3. A shear knife as claimed in claim 1 wherein the longitudinally extending opening is oblong in cross section with generally parallel sides and the lifting lug has a corresponding cooperating cross section.
 4. A shear knife as claimed in claim 3 wherein the locking means is a transverse pin passing through openings in the shear knife and lifting lug. 